Chainsaw Repair

You mention 'a piece of a cutting tool' was it large enough to cover the entire mating surface between the jug and the case? Perhaps you could provide a picture of it. IIRC there used to be a large surface grinder I believe made by Blanchard that was used to precision surface grind things like the mating surfaces for hydraulic pumps for large machinery, is that the type of cutter you were using?

The cutting tool was 1/4 square cutting tool for a lathe, I used it just to lay on the case, shine a light behind it and look for gaps.

FWIW the Blanchard company made all kinds of precision grinders both surface type and centerless.I have worked on several that side ground connecting rods for auto engines .

I've heard of grinding aluminum  but never seen it done .Aluminum is a material that can be precision machined to almost a mirror finish .Fact being I have a collection of synthetic diamond tooling once used to machine automobile pistons .Some as a matter of fact are real industrial diamond but not gem quailty made be DeBeers .

use wd 40 when grinding or cutting al, problem solved.